With the rapid development of the flat panel display technology, an Organic Light Emitting Display (OLED for short) has been widely applied due to its excellent characteristics such as self-luminescence, high brightness, wide viewing angle, and rapid response. In order to drive organic light emitting devices in an OLED to emit light, an OLED panel includes a scan driving circuit containing a plurality of cascaded shift registers.
A circuit structure of a shift register in the related art and its corresponding operating sequence are shown in FIG. 1 and FIG. 2, respectively. FIG. 1 is a circuit structure diagram of a shift register provided in the related art and FIG. 2 is an operating sequence diagram of the shift register provided in the related art. It has been found that there is a risk of breakdown of the transistor M1 in the shift register due to high voltage drop between its first terminal and second terminal.